Pooled CRISPR screening is a powerful method for identifying genes involved in complex biological mechanisms such as cell proliferation, cell survival and drug/toxin resistance. The Chromium Single Cell Gene Expression Solution combined with Feature Barcode technology provides a high-throughput and scalable approach to assess the effects of perturbations on gene expression via direct capture of gRNAs and polyadentlyated mRNAs from the same single cell. This powerful solution allows analysis of regulatory gene networks and pathways involved in development and disease, resolve complex biological pathways and dissect cellular regulation at an unprecedented scale with single cell resolution.